


One Good Prank Deserves Another

by UselessReptileWrites



Series: Dreemurr Siblings Three [1]
Category: Undertale (Video Game)
Genre: Gen, Humor, Mentions of No Mercy Route, Post-Undertale Pacifist Route - "I want to stay with you.", Pranks and Practical Jokes, SAVED Asriel Dreemurr, SAVED Chara Dreemurr, Siblings
Language: English
Status: Completed
Published: 2018-09-07
Updated: 2018-09-07
Packaged: 2019-07-07 12:50:13
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,748
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15908607
Author URL: https://archiveofourown.org/users/UselessReptileWrites/pseuds/UselessReptileWrites
Summary: Chara has had it with Sans’s pranks and decides to seek revenge. Asriel isn't so sure about this attempt at retaliation, but goes along with it. Frisk just wants a good laugh.





	One Good Prank Deserves Another

**Author's Note:**

> So I run an ask blog for these three, and I remembered a past response I made and how I very much would like to write it. And then I realized now I have an account on here where I could!

If you didn’t know Chara very well, then you wouldn’t be able to tell anything was wrong as they entered Asriel’s room. They didn’t slam the door, they didn’t drop dramatically on the bed, they didn’t even huff.

But Asriel had spent years with them. He’d lived with them three years in the Underground, and then spent years’ worth of resets looking back on their actions, cementing each detail in his mind so he couldn’t forget anything about his sibling and best friend.

So he could tell, from the tenseness under their eyes and how forced their smile was, that they were irritated with something.

 _Did I do something wrong?_ He started thinking of what he did to upset them, but caught himself. There was no possible way for him to have upset them when they and Frisk were out of the house all day while he stayed home to do a little work on his project. Plus, they’d long since stopped and apologized for pressuring him to change his behavior to fit what they thought would be best for him as a prince.

“What’s wrong?” he asked as they settled on his bed, most likely since he was sitting at his desk chair, the only proper seat in the room.

Chara shook their head. “You do not have to worry about me.”

Asriel hummed as he considered this. Obviously they were irritated, but they had some kind of dislike toward sharing any emotion, not just the negative ones. It wasn’t something he felt comfortable remarking on, given the facts that they’d gotten better about it since their revival and that he himself held stuff back if he felt it might upset others. But still, it was a lot of work to figure them out sometimes.

 _Gosh, I wish they’d open up more and just tell me what’s made them upset,_ he thought as he scratched an ear without thinking.

“So, where did you and Frisk go today?” he asked. Hopefully that would narrow down what was bothering them.

As they continued to speak, Asriel noted Chara was speaking slightly faster than their usual calm, clear narration. “Frisk convinced me to go with them to visit Sans and Papyrus.”

Asriel nodded. He wanted to tell them that they didn’t have to go if they didn’t want to, but right now he was slightly afraid that they’d take it as a scolding, and they were upset enough as it was. “What happened?” He hoped this was neutral enough.

They shrugged. “While we were there, Sans offered us a seat on the couch.”

“Oh, no.” Asriel didn't have to know the rest of the story to know how it went.

Chara took a deep breath. He could see the irritation in their eyes. “Oh, yes. It was the old whoopee cushion prank. And I could not even do anything about it, at least without being rude.”

“That stinks.” It really did. He knew from experience that pranks you were inevitably going to fall for felt worse than the ones you were honestly tricked into. 

“I suppose that pranks are not as amusing to me as they are to him.” They paused to pluck a strand of loose hair from their head, and then glanced around the bases of the walls, looking for a trash can.

Asriel got up from his chair to grab the bin for them, and they discarded the hair with a nod of gratitude. “Well, maybe if you asked Mom to tell him not to prank you? I mean, they’re good friends, and he doesn’t strike me as the unreasonable kind.” And it wasn’t as if Sans had a shortage of people who wouldn’t mind being pranked; Frisk in particular thought they were the funniest things ever.

“I prefer not to involve her in my troubles.” Asriel took it as they didn’t want to risk making her upset with Sans. “Anyways, I am considering something that would give him a taste of his own medicine.”

Asriel tilted his head. “What?” He hadn’t heard that phrase before.

“It means that I shall get him back by a prank of my own.”

Asriel had a bad feeling about this.

But as he opened his mouth to say this, a firm rapping on the door announced Toriel’s presence.

“Asriel? Chara? It is time for dinner.”

“Okay,” he said out of habit. Before he could turn back to tell Chara how he felt about their declaration, they were already moving toward the door.

Well, he was always overthinking things these days, wasn’t he? Surely nothing could go wrong with Chara just thinking of a prank.

* * *

If Asriel told the truth, he’d nearly forgotten the incident until, a couple weeks later, Chara asked their mother if they could take a walk to the corner store.

Toriel turned and raised an eyebrow. “Are you quite sure, my child?”

Asriel could get her surprise. Chara hardly went anywhere unprompted, usually just tagging along if someone happened to be going a place they could tolerate.

“I am sure, Mother.” They’d already dressed themself in a light coat, a fancy lilac one with the Delta Rune embroidered with gold on its chest, some gloves of the same color, and a pair of glossy dress shoes. “I have some business to which I must attend.”

“Can I come?” Asriel winced as everyone glanced at him, and stared at his feet. It wasn’t as if anyone looked angry. No one would be angry at him for something as simple as asking if he could come along to the store. He just hadn’t expected to ask, that was all.

“Yes, I could do with the company.” Asriel glanced up to catch the end of Chara’s nod. They turned back to Toriel. “May we?”

Toriel glanced between them and nodded. “Very well, but do be careful. And remember to cross with the walk light!”

Asriel nodded. “Don’t worry, Mom, we will!” Frisk had been very insistent that he pay attention both to walk lights and whether or not cars were actually obeying them after one of the times they’d had to load a save. Apparently, their friend Monster Kid had ran across the street without looking, not even knowing what a walk light was, and they'd been injured. However, there weren’t very many cars around Home the Third yet; not many monsters had cars or licenses yet, and it was a bit out of the way for most humans openminded enough to visit.

Chara waited by the door as he pulled his coat on. They didn’t look impatient, but still he walked to the door without putting on his scarf, instead choosing to wrap it around his neck as he walked outside.

They followed him out onto the path, gave a nod in greeting to Frisk as they passed them as they drew on the sidewalk, and went on their way down the road.

“So, why are we going to the corner store?” Asriel asked as they rounded the corner and ventured out of sight of their house.

Chara raised their hands to sign. “Do you remember what I told you about the prank Sans pulled on me a week or two ago?”

Asriel nodded, feeling the unease come back. He tried to distract himself by the crunchiness of the orange leaves underfoot, but it didn’t work at all.

 _Come on,_ he told himself. _They won’t try anything like the pie prank again. They’d surely make their plan as harmless as possible._

“I have come up with an idea of how to prank him back.”

Asriel swallowed. This didn’t sound good. “How?” he asked, and was surprised at how neutral his tone was.

Chara hummed, a little thoughtful sound. “The corner store, I believe, sells whoopee cushions smaller than the usual kind.”

Asriel wrinkled his nose. That he hadn’t expected. Chara’s pranks were usually wittier than this. This would normally be beneath them, being too “vulgar” for their tastes.

But it was Sans’s go-to prank, and if there was one thing Chara liked, it was making their point. What greater point was there than to use someone's favorite trick against them?

“It sounds like a good idea.” He tried to pick his words carefully without sounding like he was. “But you know he’s a pretty observant person.” Boy, did Asriel know that for a fact.

Chara, meanwhile, was watching a couple of humans walking on the sidewalk on the other side of the street, trying not to be too obvious about it. “It is worth trying. Do you not agree?”

Well, Asriel had to admit a whoopee cushion was pretty harmless. Even if it backfired, what could happen? Normally he might have to fear a second prank directed toward them as reprisal, but Sans was such a laidback monster that it wasn’t a big risk with him.

“I guess.” He wrapped his scarf around his neck one more time.

Chara nodded. “Then we must hurry to the store before it closes.” And they picked up the pace.

Asriel broke into a light jog to catch up, ignoring how his scarf started to unravel itself in response.

* * *

A few minutes later and he and Chara were leaving the store, the bell chiming delicately as the door let them through. Chara pulled the small whoopee cushion from its plastic wrapper and shoved the plastic into their pocket before they examined the item with a critical eye.

“This should be small enough to fit in my glove,” they muttered to themself, so quietly Asriel could barely hear them. “Though that does limit when I can pull this off.”

They inflated the whoopee cushion, but to Asriel’s dismay they inflated it all the way.

“Uh, you might want to keep it only partially inflated.” He stroked the ends of his scarf as they looked at him with curiosity. “If you don’t, your mittens will look sort of all lumpy, and Sans will notice.”

Chara nodded. “Of course.” They almost grimaced and pressed down on the whoopee cushion, and it made a wet and gross raspberry sound as it deflated to a less noticeable size. As they tucked it into their mitten, they asked, “How did you learn to use these? I do not recall us having them.”

Asriel bit his lip. “Well, I kind of picked up when I was a flower.”

Chara nodded. “Sorry.” The sign was short and contrite, and they immediately set off down the sidewalk at a brisk pace, an obvious attempt at avoiding eye contact. They’d likely remembered that he’d learned everything about monsters worth knowing, and how he’d accomplished that.

Asriel winced to himself. _I should’ve made something up._ He tried very hard not to kick at the fallen leaves in frustration at himself. _But they won’t accept my apology, and they never listen when I tell them me doing that isn’t their fault. What can I do?_

But he knew them well enough to know what cheered them up, even if they wouldn’t admit it. And it was familiarity.

“Hey, Chara, isn’t it weird that autumn makes everything look like Home? You know, Old Home?” He’d certainly been surprised, the first time he'd seen autumn come around. All Home the Third needed was to be made entirely from purple stone and it’d be a complete copy, from the giant castle walls enveloping the entire city to the building style.

It seemed like names weren’t the only ideas their dad reused.

Chara glanced around at the plants around them, the leaves piling up on the roadsides. “Actually, I always did find Old Home’s trees the weird ones.” They bit their lip and narrowed their eyes ever so slightly as they considered this. “Why did they grow leaves if they were just to wither and fall off immediately?”

Asriel shrugged, stifling the irritation of not being able to know that.

“It does not make sense.” They gave an almost petulant shake of their head.

Asriel fought back a smile as he realized the opening they’d given him. “Like how you humans grow hair only to lose them later?”

They turned to face him, one eyebrow arching over their eye in carefully cultivated disdain. “As if you are one to talk. You boss monsters leave fur everywhere.”

“Not everywhere.” He pouted, mostly to help hide his grin.

Chara sniffed, loud and deliberate enough so that no one could mistake it as anything but the attempt at aloofness it was. “Just in the shower, then.”

Asriel mimicked their posture, from the perfectly straightened spine to the long, purposeful strides. “Water does dislodge it from our bodies. It’s perfectly natural and, unlike human hair, it dissolves shortly afterward.” One of the perks of being made of magic was that you couldn’t be blamed for clogged sink and shower drains.

The corner of their smile twitched further toward sincerity. “Is that why you and Mother leave it in our food and not bother to pick them out?”

Asriel groaned, letting himself relax at that, as Chara sometimes jokingly referred to such a cutting statement, “burn.” “I don’t mean to, but all this fur just won’t stop falling out when we’re cooking.” It was like his hair knew whenever he was preparing food and all tried to shed at once.

Chara tilted their head back a degree or two, a victorious posture if he’d ever seen one. “A hairnet might be in order.”

Asriel scoffed and shook his head, letting his smile show. “Over my whole body?”

Finally, Chara’s smile was totally, completely honest. “But of course. After all, you are the hair to the throne.”

He would linger about how he felt about his position over another day, because that– _that_ –that was just too awful. He couldn’t help but giggle, even as he buried his face into his hands. “That was worse than Mom’s, Chara.” He had to choke the words out between laughs.

Chara nodded and placed their hands behind their back, their stride almost becoming a strut of victory and pride.

Finally, they returned back home, and Asriel saw the spark of mischief in Chara’s eyes as they saw Frisk still in the walkway with their chalk. It looked like Chara had found their test subject for the prank. 

“What are you drawing, Frisk?” they asked, and walked right up to Frisk.

“Just doodling.” Frisk set the chalk down and wiped their hands on their jeans.

Chara held out their hand for Frisk to help themself up with.

Frisk took it.

The whoopee cushion announced its presence to the neighborhood, and Frisk lurched back, laughing uncontrollably.

“Chara!” They grabbed at their ribs and pointed at them.

Chara shook their head, clearly amused. Well, clearly if you were as observant as Asriel. “It does not do for a prinxe to be making those sounds, sibling.”

“Speak for yourself!” They calmed down and squinted down at Chara’s mitten. “Where’d you get it? Did you borrow it from Sans?”

“No, but I did get it for him.” Their smile shifted into something sly. “I do ask that you keep this between us.”

Frisk tilted their head, then grinned. “Only if I can see you get him.”

Chara stuck out their hand. “Acceptable.”

With the force that Frisk took it, it sounded like they were high-fiving instead of shaking hands. “And if Sans catches onto you or something, I can always load a save and tell you it’s a bad idea!”

Asriel squinted at Chara. Their demeanor had changed just barely, so slightly even he had a hard time telling. They’d shifted their weight a little more toward their heels, and their smile felt a little forced. But otherwise, he couldn’t see any other differences.

“That is not necessary,” Chara said, voice soft but firm. “If it fails, it fails. I do not need a do-over.”

Frisk nodded, looking slightly disappointed but still eager. “So when are you going to do it?”

Chara shrugged. “It will not be for a while, but rest assured, you will be witness.”

* * *

It wasn’t until snow lightly dusted the ground when Chara decided it was time to pull off their prank.

Toriel had told the three that a meeting would keep her at school later than usual, and Papyrus and Sans were going to pick them up and drive them to their house to wait for her to pick them up. No sooner had Toriel left the room when Chara had signed to him and Frisk that they’d be putting their plan into action.

Chara met him at the front door, mitten already pulled on, the whoopee cushion undoubtedly underneath. A minute later, Frisk ran up, their backpack clattering on their shoulders.

“Are they here yet?” they signed.

Asriel glanced out the door’s window. “Yeah, I see Papyrus’s car.”

Frisk clapped their hands over their mouth, smile as wide as it can go.

“I suppose we should go out to greet them.” And Chara glided out the door.

Asriel followed, pouring all his energy into pretending that this was a normal occurrence, that Chara had nothing at all planned. Thankfully, Frisk had picked on the cue as well and was making a valiant try to hide any anticipation beneath the normal excitement to see two of their friends.

“GREETINGS, HUMANS, ASRIEL,” Papyrus said as they approached the car. He was standing out in front of his bright red convertible, which currently served as a solid surface for Sans to lean against. “WAS YOUR DAY AT SCHOOL BOTH SUITABLY FUN AND EDUCATIONAL?”

Frisk nodded, hair flying all over from the energy behind it. “Yep!” They straightened up with pride. “We got our tests back today, and I’m doing really well!”

“As are Asriel and I,” Chara added. Their hand was just the slightest bit tense compared to usual, but Asriel wasn’t sure how he could bring their attention to it while not alerting Sans and Papyrus to it as well.

“on what?” It didn’t take someone good at reading people to tell Sans was just searching for an opportunity to make a joke and make Papyrus pretend to be upset.

“Math,” Asriel said, and braced himself for the joke.

Sans shrugged. “no wonder you all did well. you always did look at things from another angle.”

“SANS!” Papyrus stomped his foot and glared down at him, though Asriel could see the smile plain on his face.

“I thought it was good,” Chara said. Asriel glanced over as they moved over toward him. “High five, pal.”

Sans stared at their hand. “ok.” And he removed his hand from his pocket and gave them their high-five.

Nothing happened.

Chara stared at their hand, not even moving it as they tried to understand how Sans could give them a high five without setting off the trap. 

“say, bro, why don't you give them a high-five as well?” Asriel could hear the mischief buried beneath Sans's encouraging tone. “They did do well on their test, after all.”

“I SUPPOSE THAT I CAN'T BEGRUDGE THEM A SHOW OF FRIENDSHIP FROM SOMEONE AS GREAT AS ME, EVEN IF THEY DID ENCOURAGE YOUR PUNFOOLERY,” Papyrus said.

Chara opened their mouth, maybe to warn him, but whatever they had to say came too late as Papyrus fell for the trick.

The whoopee cushion went off, loud and clear.

For a moment Asriel wondered if he’d maybe somehow gained the ability to stop time, regardless of being a monster again without the ability to handle determination. Papyrus’s face stayed frozen in the wide grin, while Chara stared at their mitten with the ultimate resignation to their fate.

Sans was just smirking.

Then it all seemed to start moving again at once. Frisk slapped their hands over their mouth as loud laughter burst out of them, and Papyrus retracted his hand to place on his hip.

“CHARA, I EXPECTED BETTER OF YOU THAN TO RESORT TO SUCH CHILDISH TRICKERY FOR CHEAP LAUGHS!” Asriel didn’t think he could remember Papyrus using such a scolding voice on anyone but his brother.

He couldn’t help but laugh, at Chara still staring at their mitten in shock and Papyrus devolving into a lecture as Frisk and Sans both laughed.

“AND YOU!” Papyrus turned to Sans with a stern glare. “DON’T THINK I AM LETTING YOU OFF THE HOOK! YOU AREN’T SETTING A GOOD EXAMPLE FOR THE CHILDREN WITH YOUR SHENANIGANS!”

“come on, bro, there’s no shame in laughing.” Sans shrugged. “that prank was a real gas.”

As Papyrus continued his lecture, having all but forgotten Chara in his rant, Asriel saw Frisk step up beside Chara.

“You sure you don’t want me to load?” Their signs were discreet, but clear enough to make Asriel pause. He didn’t want to forget this. He knew that Chara was embarrassed, but not that badly, and they’d likely laugh over it later.

Chara raised their own hands to reply. “I am sure.”

Asriel didn’t realize he was sighing with relief until he caught sight of his breath, visible in the winter air, curling like smoke from his mouth.

Oh, yeah, it was cold.

“We should get in the car before Frisk and Chara freeze,” he said. It was easy for him to forget that his siblings could get cold, being coated in extra fur as he was. He could guess Sans and Papyrus could, too, since he doubted monsters without skin would be that bothered by the winter.

Papyrus sighed and jabbed a hand toward his brother. “WE SHALL CONTINUE THIS CONVERSATION LATER, WHEN OUR YOUNG FRIENDS AREN’T IN DANGER OF HYPOTHERMIA.” He turned to Frisk and Chara to shoo them toward the car. Frisk hopped in, seemingly unbothered. Chara almost stormed into the seat next to them.

Asriel sat on the end, kicking the snow from his feet before setting them onto the tan floormat inside. He closed the door, sealing the cold out, and buckled in.

“You okay, Chara?” Asriel asked, noticing them staring at their hand incredulously.

“There is no possible way he should have avoided the whoopee cushion.” They kept their hands low, so that their signs wouldn’t be as visible from the rearview mirror. “It is not possible.”

Asriel could only shrug. Maybe he didn’t know all the mysteries worth knowing about all monsters.

But while the thought made him itch with the desire to know what else he’d missed, not let a single scrap about the monsters go unknown or unnoticed, he was having a good time.

And wasn’t that enough?

**Author's Note:**

> Constructive criticism is welcomed, as always!


End file.
